1 //===-- String to integer conversion utils ----------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #ifndef LLVM_LIBC_SRC_SYS_WAIT_WAIT4IMPL_H
10 #define LLVM_LIBC_SRC_SYS_WAIT_WAIT4IMPL_H
11
12 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
13 #include "src/__support/common.h"
14 #include "src/__support/error_or.h"
15 #include "src/errno/libc_errno.h"
16
17 #include <signal.h>
18 #include <sys/syscall.h> // For syscall numbers.
19 #include <sys/wait.h>
20
21 namespace LIBC_NAMESPACE {
22 namespace internal {
23
24 // The implementation of wait here is very minimal. We will add more
25 // functionality and standard compliance in future.
26
wait4impl(pid_t pid,int * wait_status,int options,struct rusage * usage)27 LIBC_INLINE ErrorOr<pid_t> wait4impl(pid_t pid, int *wait_status, int options,
28 struct rusage *usage) {
29 #if SYS_wait4
30 pid = LIBC_NAMESPACE::syscall_impl<pid_t>(SYS_wait4, pid, wait_status,
31 options, usage);
32 #elif defined(SYS_waitid)
33 int idtype = P_PID;
34 if (pid == -1) {
35 idtype = P_ALL;
36 } else if (pid < -1) {
37 idtype = P_PGID;
38 pid *= -1;
39 } else if (pid == 0) {
40 idtype = P_PGID;
41 }
42
43 options |= WEXITED;
44
45 siginfo_t info;
46 pid = LIBC_NAMESPACE::syscall_impl<pid_t>(SYS_waitid, idtype, pid, &info,
47 options, usage);
48 if (pid >= 0)
49 pid = info.si_pid;
50
51 if (wait_status) {
52 switch (info.si_code) {
53 case CLD_EXITED:
54 *wait_status = W_EXITCODE(info.si_status, 0);
55 break;
56 case CLD_DUMPED:
57 *wait_status = info.si_status | WCOREFLAG;
58 break;
59 case CLD_KILLED:
60 *wait_status = info.si_status;
61 break;
62 case CLD_TRAPPED:
63 case CLD_STOPPED:
64 *wait_status = W_STOPCODE(info.si_status);
65 break;
66 case CLD_CONTINUED:
67 *wait_status = __W_CONTINUED;
68 break;
69 default:
70 *wait_status = 0;
71 break;
72 }
73 }
74 #else
75 #error "wait4 and waitid syscalls not available."
76 #endif
77 if (pid < 0)
78 return Error(-pid);
79 return pid;
80 }
81
82 } // namespace internal
83 } // namespace LIBC_NAMESPACE
84
85 #endif // LLVM_LIBC_SRC_SYS_WAIT_WAIT4IMPL_H
86